
import java.awt.*;
import java.awt.event.KeyEvent;
import java.util.Random;

public class Tank {

    public static final int XSPEED = 5;
    public static final int YSPEED = 5;

    public static final int WIDTH = 30;
    public static final int HEIGHT = 30;

    private boolean live = true;

    TankClient tc;

    private final boolean good;

    private int x, y;

    private static Random r = new Random();

    private boolean bL = false, bU = false, bR = false, bD = false;

    enum Direction {L, LU, U, RU, R, RD, D, LD, STOP}

    private Direction dir = Direction.STOP;

    private Direction ptDir = Direction.D;

    // 定义坦克运动随机运动步数
    private int step = r.nextInt(15) + 3;


    public Tank(int x, int y, boolean good) {
        this.x = x;
        this.y = y;
        this.good = good;
    }

    // 坦克构造器增加参数，为敌方坦克移动放方向进行初始化
    public Tank(int x, int y, boolean good, Direction dir, TankClient tc) {
        this(x, y, good);
        this.dir = dir;
        this.tc = tc;
    }

    public void draw(Graphics g) {
        if (!live) {
            if (!good) {
                tc.tanks.remove(this);
            }
            return;
        }

        Color c = g.getColor();
        if (good) g.setColor(Color.RED);
        else g.setColor(Color.BLUE);
        g.fillOval(x, y, WIDTH, HEIGHT);
        g.setColor(c);

        switch (ptDir) {
            case L:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x, y + Tank.HEIGHT / 2);
                break;
            case LU:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x, y);
                break;
            case U:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x + Tank.WIDTH / 2, y);
                break;
            case RU:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x + Tank.WIDTH, y);
                break;
            case R:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x + Tank.WIDTH, y + Tank.HEIGHT / 2);
                break;
            case RD:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x + Tank.WIDTH, y + Tank.HEIGHT);
                break;
            case D:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x + Tank.WIDTH / 2, y + Tank.HEIGHT);
                break;
            case LD:
                g.drawLine(x + Tank.WIDTH / 2, y + Tank.HEIGHT / 2, x, y + Tank.HEIGHT);
                break;
        }

        move();
    }

    void move() {
        switch (dir) {
            case L:
                x -= XSPEED;
                break;
            case LU:
                x -= XSPEED;
                y -= YSPEED;
                break;
            case U:
                y -= YSPEED;
                break;
            case RU:
                x += XSPEED;
                y -= YSPEED;
                break;
            case R:
                x += XSPEED;
                break;
            case RD:
                x += XSPEED;
                y += YSPEED;
                break;
            case D:
                y += YSPEED;
                break;
            case LD:
                x -= XSPEED;
                y += YSPEED;
                break;
            case STOP:
                break;
        }

        if (this.dir != Direction.STOP) {
            this.ptDir = this.dir;
        }

        if (x < 0) x = 0;
        if (y < 30) y = 30;
        if (x + Tank.WIDTH > TankClient.GAME_WIDTH) x = TankClient.GAME_WIDTH - Tank.WIDTH;
        if (y + Tank.HEIGHT > TankClient.GAME_HEIGHT) y = TankClient.GAME_HEIGHT - Tank.HEIGHT;

        // 使敌方坦克不规则运动
        if (!good) {
            // 将枚举类转换为数组
            Direction dirs[] = Direction.values();
            // 如果步数清零
            if (step == 0) {
                // 将 step 重新赋值一个随机步数
                step = r.nextInt(13) + 3;
                // 取出数组长度中一个随机数
                int rn = r.nextInt(dirs.length);
                // 取出数组中对应下标的方向
                dir = dirs[rn];
            }
            step--;
            // 使敌方坦克可以发射子弹，并能调节火力
            if (r.nextInt(40) > 37) {
                this.fire();
            }
        }
    }

    public void keyPressed(KeyEvent e) {
        int key = e.getKeyCode();
        switch (key) {
            case KeyEvent.VK_LEFT:
                bL = true;
                break;
            case KeyEvent.VK_UP:
                bU = true;
                break;
            case KeyEvent.VK_RIGHT:
                bR = true;
                break;
            case KeyEvent.VK_DOWN:
                bD = true;
                break;
        }
        locateDirection();
    }

    void locateDirection() {
        if (bL && !bU && !bR && !bD) dir = Direction.L;
        else if (bL && bU && !bR && !bD) dir = Direction.LU;
        else if (!bL && bU && !bR && !bD) dir = Direction.U;
        else if (!bL && bU && bR && !bD) dir = Direction.RU;
        else if (!bL && !bU && bR && !bD) dir = Direction.R;
        else if (!bL && !bU && bR && bD) dir = Direction.RD;
        else if (!bL && !bU && !bR && bD) dir = Direction.D;
        else if (bL && !bU && !bR && bD) dir = Direction.LD;
        else if (!bL && !bU && !bR && !bD) dir = Direction.STOP;
    }

    public void keyReleased(KeyEvent e) {
        int key = e.getKeyCode();
        switch (key) {
            case KeyEvent.VK_CONTROL:
                fire();
                break;
            case KeyEvent.VK_LEFT:
                bL = false;
                break;
            case KeyEvent.VK_UP:
                bU = false;
                break;
            case KeyEvent.VK_RIGHT:
                bR = false;
                break;
            case KeyEvent.VK_DOWN:
                bD = false;
                break;
        }
        locateDirection();
    }

    public Missile fire() {

        // 判断我方坦克阵亡后不能在发射炮弹
        if (!live) {
            return null;
        }
        int x = this.x + Tank.WIDTH / 2 - Missile.WIDTH / 2;
        int y = this.y + Tank.HEIGHT / 2 - Missile.HEIGHT / 2;
        Missile m = new Missile(x, y, good, ptDir, this.tc);
        tc.missiles.add(m);
        return m;
    }

    public Rectangle getRect() {
        return new Rectangle(x, y, WIDTH, HEIGHT);
    }

    public boolean isLive() {
        return live;
    }

    public void setLive(boolean live) {
        this.live = live;
    }

    public boolean isGood() {
        return good;
    }
}
